相关疑难解决方法(0)

什么是神奇的数字？

为什么要避免？

有适合的情况吗？

我正在尝试检测设备当前是否正在充电,但此代码始终将isCharging变量设置为false:

public class PowerReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent)
    {
        int status = intent.getIntExtra(BatteryManager.EXTRA_STATUS, -1);
        boolean isCharging = status == BatteryManager.BATTERY_STATUS_CHARGING || status == BatteryManager.BATTERY_STATUS_FULL;

        int chargePlug = intent.getIntExtra(BatteryManager.EXTRA_PLUGGED, -1);
        boolean usbCharge = chargePlug == BatteryManager.BATTERY_PLUGGED_USB;
        boolean acCharge = chargePlug == BatteryManager.BATTERY_PLUGGED_AC;

        if (isCharging)
        {
            Toast.makeText(context, "Charging", Toast.LENGTH_LONG).show();
        } else {
            Toast.makeText(context, "Not charging", Toast.LENGTH_LONG).show();
        }

    }

}